【题解】 bzoj2460: [BeiJing2011]元素 （线性基）

//It is coded by Ning_Mew on 5.29
#include<bits/stdc++.h>
#define LL long long
using namespace std;

const int maxn=1007;

int n;
LL A[maxn];
struct Node{
  LL num;int val;
}s[maxn];
LL ans=0;

bool cmp(const Node &x,const Node &y){return x.val>y.val;}

bool check(int k){
  bool kk=false;
  for(int i=60;i>=0;i--){
    if((s[k].num>>i)&1){
      if(!A[i]){
        A[i]=s[k].num; kk=true; break;
      }else{
        s[k].num=(s[k].num^A[i]);
      }
    }
  }return kk;
}
int main(){
  scanf("%d",&n);
  for(int i=1;i<=n;i++){
    scanf("%lld%d",&s[i].num,&s[i].val);
  }
  sort(s+1,s+n+1,cmp);
  
  for(int i=1;i<=n;i++){
    if(check(i))ans+=s[i].val;
  }
  printf("%lld\n",ans);
  return 0;
}